Log the change of working directory

We initially change the current directory to the dotfile directory, but
does not show this to the user. Log it to the console if the program is
run in verbose mode.

Signed-off-by: Marcus Karlsson <mk@acc.umu.se>
Only change directory if needed

We initially change the current working directory to the dotfile
directory. This is not necessary in the case where the program is
launched with the dotfile directory already set to the current
working directory. Check if the current directory is equal to the
dotfile directory and only change to it if they don't match.

Signed-off-by: Marcus Karlsson <mk@acc.umu.se>